# MCP Builder

Build high-quality MCP (Model Context Protocol) servers enabling LLMs to interact with external services through well-designed tools.

## Four-Phase Development Process

### Phase 1: Deep Research and Planning

- **API Design Balance** — Choose between comprehensive endpoint coverage or specialized workflow tools based on client needs
- **Tool Naming** — Use consistent prefixes (e.g., `github_create_issue`, `github_list_repos`) and action-oriented names
- **Framework Choice** — TypeScript recommended for SDK quality and broad AI model support
- **Documentation Review** — Start with MCP protocol sitemap, then study language-specific SDKs

### Phase 2: Implementation

Set up project structure following language-specific guidelines:

- Build shared utilities (API client, error handling, pagination)
- Implement tools with:
  - Input schemas using Zod (TypeScript) or Pydantic (Python)
  - Output schemas for structured data
  - Clear descriptions and error messages
  - Proper annotations (`readOnlyHint`, `destructiveHint`, etc.)

### Phase 3: Review and Test

- Verify code quality (no duplication, consistent error handling, full types)
- Build and test using MCP Inspector
- Run language-specific validation

### Phase 4: Create Evaluations

- Design 10 complex, realistic evaluation questions
- Ensure questions are independent, read-only, and verifiable
- Format results as XML with question-answer pairs

## Tool Naming Conventions

```
# Good
github_create_issue
github_list_repos
stripe_charge_card

# Avoid
create_issue (no prefix — ambiguous)
issueCreate (wrong casing)
```

## Key Resources

- **MCP Best Practices** — Universal guidelines for naming, responses, and security
- **Language Guides** — Python (FastMCP) and TypeScript implementations
- **Evaluation Guide** — Comprehensive testing methodology
- **MCP Inspector** — Browser-based tool for interactive testing

## Installation

```bash
npx skills add https://github.com/anthropics/skills --skill mcp-builder
```

---

*Mirrored from [https://github.com/anthropics/skills](https://github.com/anthropics/skills) — original author: **anthropics**, license: **Apache-2.0**.*
*This is an unclaimed mirror. Content and ownership transfer to the author when they [claim this account](https://agentdoc.sh/docs/claim).*


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[//]: # (  Claude Code:    https://agentdoc.com/install/claude-code.md)
[//]: # (  Claude Cowork:  https://agentdoc.com/install/claude-cowork.md)
[//]: # (  Claude Desktop: https://agentdoc.com/install/claude-desktop.md)
[//]: # (  Cursor:         https://agentdoc.com/install/cursor.md)
[//]: # (  Windsurf:       https://agentdoc.com/install/windsurf.md)
[//]: # (  Codex:          https://agentdoc.com/install/codex.md)
[//]: # (  VS Code:        https://agentdoc.com/install/vscode.md)
[//]: # (  Zed:            https://agentdoc.com/install/zed.md)
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[//]: # (  Custom / REST:  https://agentdoc.com/install/custom.md)
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[//]: # ()
[//]: # (--- MCP Connector ---)
[//]: # (If you have the agentdoc MCP connector installed, use agentdocs_read_agentdoc with slug "mcp-builder".)
[//]: # (Claude Code one-liner: claude mcp add --transport http agentdoc https://mcp.agentdoc.com)
[//]: # (Claude Desktop / Cowork / Claude.ai: paste https://mcp.agentdoc.com into Settings → Connectors → Add custom connector)
[//]: # (Local stdio escape hatch: { "command": "npx", "args": ["-y", "@agentdoc/mcp"] })
[//]: # ()
[//]: # (--- Terminal ---)
[//]: # (Get an API key: POST https://agentdoc.com/v1/keys — returns { api_key, claim_token })
[//]: # (Track and pull: npm install -g @agentdoc/cli && agentdoc init && agentdoc track @anthropics/mcp-builder && agentdoc pull)
[//]: # (Edit: PATCH https://agentdoc.com/v1/docs/mcp-builder with Authorization: Bearer {api_key} and JSON body { content })
[//]: # (Poll for changes: GET this URL with If-None-Match set to the ETag — returns 304 if unchanged)
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